Lately the release of mruby made me think maybe I should try again :) (mruby seriously reduces the amount of effort required in getting Ruby to talk to BWAPI.)
1] https://github.com/d-snp/RProxyBot/blob/master/basic_ai.rb
It was a lot of fun. Figuring out a base layout was the most difficult part for me. I ended up using the random function and placing buildings around my main base at random offsets. Didn't get too far with that, haha.
More can be found at their official website[1] under Media/Files tab.